Northfax Intersection and Drainage Improvements

After nearly two decades of planning, a highly complicated road and drainage improvement project is underway at a busy intersection in the City of Fairfax, VA.

Branch Civil was awarded the $23.8M contract to improve safety and storm drainage at the intersection of Route 123 (Chain Bridge Road) and Fairfax Boulevard (Routes 50/29), one of the busiest crossroads in the city’s center.  This intersection is known locally as Northfax.

Because of the complexity of the project, it took city planners 15 years to get the design approved.  The road construction phases include widening Chain Bridge Road to six lanes between Fairfax Boulevard and Eaton Place while improving the lane alignments at the Northfax Intersection.  The project will also improve pedestrian safety by adding ADA ramps at all four corners and by rehabilitating all traffic signals.

The focus of this project involves addressing serious issues caused by an inadequate 1960’s-era culvert under Route 123.  Improvements consist of installing a 2,100-linear foot double barrel box culvert to replace an existing stream and improve drainage in front of a shopping center.  Some areas of the project have potentially contaminated groundwater and soil which makes testing, treatment, and disposal of the contaminated matter an ongoing process.

An even bigger challenge for Branch Civil crews is keeping water out of the excavation sites and safely re-routing it to the appropriate discharge locations.  This is being accomplished with pumps, several thousand feet of hose and concrete flumes.

To complicate matters even further, the box culvert crosses Route 123, with a detour in place to install the culvert across the road in two phases.  The culvert must run under an existing 12’ gas line and a major fiber optic duct bank.  This meant employing a special support to hold up these sensitive lines during the excavation.

Despite the intricate nature of this project, the largest ever awarded to one contractor in the city’s history, work is on track to be completed on time and on budget.